While the concept and principles of the present invention may be applicable to various types of apparatus and environments, the invention disclosed herein relates generally to press unloading apparatus and, more particularly, to press unloading devices of the type disclosed in U.S. Pats. No. 2,609,776 and 3,206,040 and to control systems therefor of the type disclosed in U.S. Pats. No. 3,474,825; 3,436,186; and 3,394,650.
It is the primary object of the present invention to provide new and improved means for lifting a formed part out of a die cavity in a press prior to removal of the part from the press cavity. To this end, a new and improved air operated control system has been devised in which the number of parts required to achieve the desired results has been reduced, the parts of the system have been arranged in a new and improved manner facilitating assembly, operation, and repair, and new and improved parts have been devised for the system.
In the presently preferred embodiment of the inventive concepts and principles, a first air operated power cylinder means actuates jaw means carried by the press unloader device between an extended part gripping position in the press cavity and a retracted position while a second air operated power cylinder means moves the jaw means between the extended part gripping position and a lift position prior to return movement of the jaw means to the retracted position. The second cylinder means is connected to high pressure air inlet hoses and exhaust hoses in series with the first cylinder means and provided with integral control means effecting a time delay of operative connection to the jaw means whereby the desired sequential operation of the apparatus is obtained. It is contemplated that the inventive concepts are also applicable to fluid operated power cylinder apparatus generally whenever a time delay operation is required. Thus, in the broadest aspects of the invention, the power cylinder apparatus may be air operated or hydraulically operated and associated with any kind of machinery, particularly material handling equipment.